This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The objective of this project is to develop an animal model of human strabismus. To provide an animal model of human exotropia, a free tenotomy was preformed in infant macaques of the medial recti. When the animals were old enough to record eye movements with video eye trackers, we measured their ductions, ocular alignment, comitance, smooth pursuit, fixation preference, and gaze stability.